Seeking Gamma

Lost in the shuffle last week was this fascinating discussion at Morningstar about a new way to judge and evaluate the relative success of one’s retirement portfolio – not through the traditional lens of alpha and beta…

From Morningstar:

The benefits from “good” financial-planning decisions are difficult to quantify. For any given portfolio, investment decisions generally can be decomposed into two primary components: beta and alpha. Beta can be defined as the systematic risk exposures of the portfolio (usually achieved through asset allocation), and alpha is the residual (skill or luck-based) component associated with the various flavors of active management, such as tactical asset allocation, security selection, and more. Alpha and beta are at the heart of traditional performance analysis; however, their impact on a successful retirement can be far less important than other financial- planning decisions.

In this article, we introduce a concept called “Gamma,” which is designed to measure the additional expected retirement income achieved by an individual investor making intelligent financial-planning decisions. Gamma is the third letter in the Greek alphabet (preceded by alpha and beta), and within financial economics, it is sometimes used as the variable denoting an investor’s degree of risk aversion. Given that Gamma is relatively unclaimed within financial literature, we seek to give it new meaning.